An existing electronic toilet can achieve rectum flushing, anus cleaning and flushing for female, and water discharged therefrom is supplied from a hot-water tank. The hot-water tank forms a circulating water way together with a circulating water pump and a seat, and the temperature of the flushing water is achieved by controlling the work of a heating tube of the hot-water tank. When the water temperature is adjusted from a high degree to a low degree by a user, such a temperature reduction can be achieved by the system only after discharging high-temperature hot-water in the hot-water tank through a spray bar first and then replenishing cold-water, or after natural cooling of the water in the hot-water tank. Both methods cannot realize rapid reduction of the water temperature.